This invention relates to an inkjet recording element. More particularly, this invention relates to a porous inkjet recording element containing porous polymeric particles.
In a typical inkjet recording or printing system, ink droplets are ejected from a nozzle at high speed towards a recording element or medium to produce an image on the medium. The ink droplets, or recording liquid, generally comprise a recording agent, such as a dye or pigment, and a large amount of solvent. The solvent, or carrier liquid, typically is made up of water, an organic material such as a monohydric alcohol, a polyhydric alcohol or mixtures thereof.
An inkjet recording element typically comprises a support having on at least one surface thereof an ink-receiving or image-forming layer, and includes those intended for reflection viewing, which have an opaque support, and those intended for viewing by transmitted light, which have a transparent support.
While a wide variety of different types of image-recording elements for use with inkjet devices have been proposed heretofore, there are many unsolved problems in the art and many deficiencies in the known products which have limited their commercial usefulness.
It is well known that in order to achieve and maintain photographic-quality images on such an image-recording element, an inkjet recording element must:
Be readily wetted so there is no puddling, i.e., coalescence of adjacent ink dots, which leads to non-uniform density
Exhibit no image bleeding
Absorb high concentrations of ink and dry quickly to avoid elements blocking together when stacked against subsequent prints or other surfaces
Exhibit no discontinuities or defects due to interactions between the support and/or layer(s), such as cracking, repellencies, comb lines and the like
Not allow unabsorbed dyes to aggregate at the free surface causing dye crystallization, which results in bloom or bronzing effects in the imaged areas
Have an optimized image fastness to avoid fade from contact with water or radiation by daylight, tungsten light, or fluorescent light
An inkjet recording element that simultaneously provides an almost instantaneous ink dry time and good image quality is desirable. However, given the wide range of ink compositions and ink volumes that a recording element needs to accommodate, these requirements of inkjet recording media are difficult to achieve simultaneously.
Inkjet recording elements are known that employ porous or non-porous single layer or multilayer coatings that act as suitable image-receiving layers on one or both sides of a porous or non-porous support. Recording elements that use non-porous coatings typically have good image quality but exhibit poor ink dry time. Recording elements that use porous coatings exhibit superior dry times, but typically have poorer image quality and are prone to cracking.
A problem with known inkjet recording elements that employ porous single layer or multilayer coatings that act as suitable image-receiving layer is dye stability during storage. In particular, dyes printed on to an inkjet receiver element tend to fade due to exposure to ozone which is present in the atmosphere.
Another problem with inkjet recording elements that employ porous single layer or multilayer coatings that act as suitable image-receiving layers is image stability under high humidity storage conditions. In particular, dyes tend to migrate through the image receiving layer during storage since the dye image receiving layer is hydrophilic and tends to absorb water from the atmosphere.
Copending U.S. patent application Ser. No. 09/608,466, filed Jun. 30, 2000, relates to an jet recording element wherein the image-receiving layer contains porous polymeric particles in a polymeric binder. However, there is a problem with this element in that during preparation of the coating solution, agglomeration of the polymeric particles occurs, which when coated, results in an element having low gloss.
JP 09207430, JP 08324101 and JP 2000/239578 relate to porous image-receiving layers for inkjet recording elements containing inorganic particles and a poly(vinyl alcohol) having various degrees of hydrolysis. However, there is a problem with these elements in that the references do not disclose the degree of hydrolysis for the poly(vinyl alcohol) necessary to provide good gloss and low cracking.
It is an object of this invention to provide an inkjet recording element that has a fast ink dry time. It is another object of this invention to provide an inkjet recording element that has good stability when exposed to ozone and high humidity conditions. It is another object of the invention to provide an inkjet recording element that has high gloss with minimal cracking.
These and other objects are achieved in accordance with the invention which comprises an inkjet recording element comprising a support having thereon an image-receiving layer comprising porous polymeric particles in a polymeric binder, the polymeric binder comprising poly(vinyl alcohol) having a degree of hydrolysis of at least about 95% and having a number average molecular weight of at least about 45,000.
By use of the invention, an inkjet recording element is obtained which has a good dry time and good stability when exposed to ozone and high humidity conditions, and has high gloss with minimal cracking.